1. Field of the Disclosure
The technology of the disclosure relates to multi-port optical connection terminals and assemblies which may be used to distribute optical signals from optical fibers.
2. Technical Background
Benefits of optical fiber use include extremely wide bandwidth and low noise operation. Because of these advantages, optical fiber is increasingly being used for a variety of applications, including but not limited to broadband voice, video, and data transmission. As a result, fiber optic communications networks include a number of interconnection points at which multiple optical fibers are interconnected. Fiber optic communications networks also include a number of connection terminals, examples of which include, but are not limited to, network access point (NAP) enclosures, aerial closures, below grade closures, pedestals, optical network terminals (ONTs), and network interface devices (NIDs). In certain instances, the connection terminals include connector ports or nodes, typically opening through an external wall of the connection terminal. The connection terminals are used to establish optical connections between optical fibers terminated from the distribution cable and respective optical fibers of one or more drop cables, extended distribution cables, tether cables or branch cables, collectively referred to herein as “drop cables,” unless specified otherwise. The connection terminals are used to readily extend fiber optic communications services to a subscriber. In this regard, fiber optic networks are being developed that deliver “fiber-to-the-curb”(FTTC), “fiber-to-the-business” (FTTB), “fiber-to-the-home” (FTTH) and “fiber-to-the-premises” (FTTP), referred to generically as “FTTx.”
In conventional FTTx deployments depicted in FIG. 1, a fiber optic network 10 is provided. The fiber optic network 10 typically delivers service to subscribers 12 through optical fiber distribution cables 14 and subscriber cables 16. For example, the fiber optic network 10 may begin at a trunk cable 18 originating from a central office 20 leading to a splitter/splice cabinet 22 in the field where a distribution cable 14 is connected. The distribution cable 14 may then be routed aerially or below ground through the residential neighborhood served by the fiber optic network 10. The subscriber cables 16 servicing individual subscribers 12 may be connected with the distribution cable 14 through terminations at mid-span access points 24, branch cables 26, connector ports 28 of multi-port splitter boxes 30, and cables 32.
FIGS. 2A to 2B depict a conventional multi-port splitter box 30 including a base 34, cover 36, and eight (8) connector ports 28. Although eight (8) connector ports 28 are shown in FIGS. 2A and 2B, multi-port splitter box 30 may have any number of connector ports 28. An optical management shelf 38 is installed into the multi-port splitter box 30 that includes an optical splitter 40 and a splice protector 42 attached to its top surface 44. An optical fiber 46 of a cable 32 enters an entry orifice 48 of the multi-port splitter box 30 and wraps around containment surfaces 50 around an orifice 52 in the top surface 44 of the optical management shelf 38. The optical fiber 46 may be spliced to an input optical fiber 54 in the splice protector 42. The input optical fiber 54 is attached to the optical splitter 40 which may have output optical fibers 56. The output optical fibers 56 include connectors 58 attached to their distal ends which may be subsequently attached to the connector ports 28 of the multi-port splitter box 30.
In general, the performance of input optical fiber 54, the output optical fibers 56, and the optical splitter 40 can be affected by mechanical and environmental issues surrounding the output splitter box 30. Mechanical issues may include small-radius bends and cyclical and episodic movements of the optical fibers. For example, standard single-mode fiber may experience high optical attenuation at small-radius bends. Environmental issues may be water when the output splitter box 30 is installed underground. Thus, the conventional approach has been to locate the input optical fiber 54, output optical fibers 56, and the optical splitter 40 inside of the output splitter box 30. This conventional approach has resulted in the multi-port splitter box 30 becoming too large in many cases for installation in the field. Ideally, the multi-port splitter box 30 should be sufficiently small in size to be able to pass through ducts and small passageways underground during installation to service subscribers 12, as an example.